Ford T F, Hermon-Taylor J, Grant D A
Clin Chim Acta. 1982 Nov 24;126(1):17-23. doi: 10.1016/0009-8981(82)90358-8.
An assay for pepsin has been developed based on the fluorometric measurement of trichloroacetic acid-soluble peptides released from casein at pH 5.3. The increase in relative fluorescence was most sensitive in the range 10-50 micrograms pepsin/l and casein hydrolysis was not affected by the addition of up to a 1000-fold molar excess of pepsinogen. This assay has been used to measure the free and total acid proteinase content of biopsies (less than 5 mg) from different areas of the gastric mucosa of rat and man. Interference by the major lysosomal acid hydrolase, cathepsin D, could be eliminated by the differential stability of pepsin and cathepsin D at acid and neutral pH. The free acid proteinase activity of biopsies from the corpus were almost identical in these species whereas the total acid proteinase activity was approximately 5-fold greater in man.
基于对在pH 5.3条件下从酪蛋白释放的三氯乙酸可溶性肽进行荧光测量，开发了一种胃蛋白酶检测方法。相对荧光的增加在10 - 50微克胃蛋白酶/升范围内最为敏感，并且酪蛋白水解不受高达1000倍摩尔过量胃蛋白酶原添加的影响。该检测方法已用于测量大鼠和人胃黏膜不同区域活检组织（小于5毫克）中的游离和总酸性蛋白酶含量。通过胃蛋白酶和组织蛋白酶D在酸性和中性pH下的稳定性差异，可以消除主要溶酶体酸性水解酶组织蛋白酶D的干扰。这些物种中胃体活检组织的游离酸性蛋白酶活性几乎相同，而人组织中的总酸性蛋白酶活性大约高5倍。
